Microcirculation and blood rheology abnormalities in chronic heart failure.

Background: Generalized restricted blood flow is hallmark of CHF of any etiology, but the extent of microcirculation restriction and the role of intrinsic blood properties in heart failure remains unknown.

Objective: The aim of this study was to estimate the microvascular blood flow and hemorheological properties in chronic heart failure to test the hypothesis that CHF patients have altered peripheral blood flow which contributes to the tissue perfusion disturbances.

Methods: Cutaneous microvascular blood flow was estimated by Laser Doppler and Optical Tissue Oximetry techniques.

Interrelation of blood coagulation and hemorheology in cancer.

Cancer progression is associated with activation of blood coagulation. Blood coagulation process, platelet hemostasis and hemorheological properties were evaluated in patients with solid tumors (n = 27) before and after surgery and in healthy control (n = 20). The main features of blood coagulation process in cancer patients were elevated intensity and shortened period of contact phase of coagulation and inhibited fibrinolysis stage.

Signaling pathways regulating red blood cell aggregation.

The exposure of red blood cells (RBC) to some hormones (epinephrine, insulin and glucagon) and agonists of α- and β-adrenergic receptors (phenylephrine, clonidine and isoproterenol) may modify RBC aggregation (RBCA). Prostaglandin E1 (PGE1) significantly decreased RBCA, and PGE2 had a similar but lesser effect. Adenylyl cyclase (AC) stimulator forskolin added to RBC suspension, caused a decrease of RBCA.

Role molecular signaling pathways in changes of red blood cell deformability.

This study was designed to investigate the dependency of the red blood cell deformability upon activation of extra- and intracellular signaling pathways. Exposures of red blood cells (RBCs) to catecholamines and to insulin led to positive change in the RBC deformability. When forskolin, a stimulator of adenylyl cyclase (AC), was added to RBC suspension, the RBC deformability was increased.